An imaging element included in an imaging device generally includes a light receiving element (a photoelectric conversion element, or a photodiode) formed in a silicon semiconductor substrate. When the wavelength of incident light is determined, the light absorption coefficient of silicon (Si) is determined uniquely. Therefore, in order to cause light, in particular light in the region from red to near-infrared, to be absorbed in the silicon semiconductor substrate with good efficiency, it is necessary to form the light receiving element in an area of the silicon semiconductor substrate located deep (specifically, for example, approximately 10 μm deep) from the light incident surface (e.g. see JP H9-331058A). This means that, when the pixel in the imaging device is miniaturized, the aspect ratio in the imaging element is increased.